JP7364735B2 - Device and method for generating forward directed shock waves - Google Patents

Description

(Cross reference to related applications)
This application claims priority to Provisional Application No. 62/521,994, filed June 19, 2017, the entire disclosure of which is incorporated herein by reference.

(Field)
TECHNICAL FIELD This disclosure relates generally to the generation of shock waves, and more specifically to the generation of shock waves within vascular or urinary structures.

(background)
The present invention relates to treating calcified lesions in blood vessels or other intraductal obstructions such as kidney stones in the ureter. One common approach to address this issue is balloon angioplasty. In this type of procedure, a catheter carrying a balloon is advanced into the vasculature along a guidewire until the balloon is aligned with the occlusion. The balloon is then pressurized in a manner that reduces or destroys the occlusion. When inflated to high pressure, angioplasty balloons may have a particular maximum diameter to which they will expand. In general, the opening within the canal beneath the afferent lesion is typically much smaller. As the pressure is increased to open the passageway for blood flow, the balloon becomes localized to the size of the opening within the calcified lesion (before it is broken open). As pressure builds up, a tremendous amount of energy is stored within the balloon until the calcified lesion ruptures or bursts. That energy is then released, causing rapid expansion of the balloon to its maximum dimension, stressing and potentially damaging the tube wall.

In recent years, the present assignee has developed systems and methods for comminuting calcific deposits in arteries and veins, for example. Such systems are described, for example, in US Pat. No. 8,956,371 and US Pat. No. 8,888,788, both of which are incorporated herein by reference. The embodiments described therein include a catheter having a balloon at its distal end, such as an angioplasty balloon, arranged to be inflated with a fluid. A shock wave generator is disposed within the balloon, which may take the form of a pair of electrodes coupled to a high voltage source at the proximal end of the catheter through a connector, for example. When the balloon is placed adjacent to areas of calcification in veins and arteries and a high voltage pulse is applied across the electrodes, a shock wave is formed that propagates through the fluid and damages the walls of the balloon and the calcification. Affect the area. Repeated pulses break up the calcium without damaging the surrounding soft tissue. Similar techniques can be used to treat kidney stones within the ureter. Shock waves generated by such systems typically propagate in all directions from the electrodes.

Arteries are sometimes completely occluded with blood clots, plaques, fibrous plaques, and/or calcium deposits. When this condition exists, the physician typically first routes a soft, thin guidewire down the artery and through the occluded area. Guidewires can be as small as 0.014 inches in diameter and typically have a soft, flexible tip to help avoid penetrating the artery wall at the corners of the artery. An angioplasty balloon is then delivered over the guidewire down the artery to the desired location of the occlusion. Unfortunately, many times, physicians are faced with chronic occlusions that are not passable with a guidewire. This occurs when the occlusion is so tight and solid that a soft guide wire cannot penetrate through it. Stiffer guidewires may be used in such cases, but they must be used very carefully as they can easily penetrate the arterial wall when pushed against chronic total occlusions. It won't happen.

Guidewires have been proposed that utilize radio frequency energy to open occlusions. Unfortunately, the heat generated by the radio frequency energy to open the blockage is intense and can damage the walls of the artery or vessel. Radio frequency energy produces a plasma that burns anything in its path. Therefore, such systems must be used carefully and must be moved continuously, without pauses, to avoid damage to the arteries or vessels. Such an approach also requires a centering mechanism to keep the plasma centered within the artery or vessel. Such centering is particularly difficult to achieve at the corners and bends of arteries or veins.

In more recent years, the present assignee has developed techniques for generating shock waves that are directed anteriorly to open a complete occlusion sufficiently to allow a guidewire and angioplasty balloon to be delivered through. , have proposed providing an electrode on the tip of the guidewire. In addition, such a system avoids damage to arteries or vessels. This rejection approach is disclosed in US Patent Application Publication No. 2015/0320432, which is also incorporated herein by reference.

The present invention relates to yet another alternative approach for generating anteriorly directed shock waves that can be integrated with an angioplasty balloon. This approach can also be used in conjunction with other types of shock wave electrodes.

US Patent No. 8,956,371 US Patent No. 8,888,788 US Patent Application Publication No. 2015/0320432

(overview)
Shockwave devices and methods for the treatment of intraluminal plaques or occlusions are described herein. The duct may include a blood vessel within the patient's vasculature or a ureter within the patient's urinary system. One example of a shock wave device includes an outer sheath and an inner member defining a guidewire lumen. The outer sheath and inner member are connected at the distal end of the device, and the volume between the outer sheath and the inner member is fillable with a conductive fluid. A first conductive wire and a second conductive wire extend along the length of the device within the volume between the outer sheath and the inner member and proximate the distal end of the device. finish. The lengths of the first and second wires are insulated and the ends of the first and second wires are uninsulated. A conductive emitter band surrounds the ends of the first and second wires, forming a first spark gap between the ends of the first wire and the emitter band; A second spark gap is formed between the part and the emitter band. When the volume is filled with a conductive fluid and a high voltage pulse is applied across the first and second wires, first and second shock waves are initiated from the first and second spark gaps. .

In some embodiments, the device further includes an insulating sheath surrounding the inner member in a region proximate the ends of the first and second wires. In some variations, the outer covering comprises an angioplasty balloon. In some examples, the emitter band is a cylindrical tube that extends closer to the distal end of the device than the first and second wires. In some examples, the device further includes a fluid pump connected to the proximal end of the device and configured to provide conductive fluid to the volume between the outer covering and the inner member; a fluid return line having an inlet proximate the distal end of the device and configured to remove conductive fluid from the volume between the outer covering and the inner member. The fluid pump and fluid return line may be configured to circulate a conductive fluid under pressure within the volume between the outer jacket and the inner member. In some embodiments, the device further includes a pressure relief valve at the outlet of the fluid return line.

In some examples, the device further extends along the length of the device within the volume between the outer covering and the inner member, terminating proximate the distal end of the device. A third conductive wire and a fourth conductive wire are included. The lengths of the third and fourth wires may be insulated, and the ends of the third and fourth wires may be uninsulated. A conductive emitter band surrounds the ends of the third and fourth wires, forming a third spark gap between the ends of the third wire and the emitter band, and forming a third spark gap between the ends of the third wire and the emitter band. A fourth spark gap may be formed between the part and the emitter band. When the volume is filled with conductive fluid and a second high voltage pulse is applied across the third and fourth wires, third and fourth shock waves are generated from the third and fourth spark gaps. May be started. In some examples, the conductive fluid includes saline or a combination of saline and a contrast agent. In some embodiments, the device further includes one or more secondary emitter bands disposed at an intermediate location of the device and configured to initiate at least a third shock wave from the intermediate location.

One embodiment of the method includes introducing a shock wave device into a tube, advancing the shock wave device into a tube such that a distal end of the shock wave device faces a first treatment area, and and applying a high voltage pulse across the second wire to generate first and second shock waves from first and second spark gaps formed between the first and second wires and the emitter band. and starting. Positioning the first and second wires and the emitter band results in first and second shock waves propagating in a substantially forward direction.

In some embodiments, the method further includes, after the applying step, further advancing the shockwave device into the vessel such that the angioplasty balloon is aligned with the first treatment region or the second treatment region. , inflating an angioplasty balloon. In some embodiments, the method further comprises: after applying, the one or more secondary emitter bands at the intermediate location of the device are aligned with the first treatment region or the second treatment region. further comprising advancing the shock wave device into the tube and initiating a third shock wave from the secondary emitter band. In some examples, the duct is a blood vessel of the patient's vasculature or a ureter of the patient's urinary system. In some examples, the first treatment area includes chronic total occlusion (CTO), peripheral calcium, or kidney stones.
The present invention provides, for example, the following.
(Item 1)
A shock wave device,
an outer covering;
an inner member, wherein the outer sheath and the inner member are connected to a distal end of the device, and a volume between the outer sheath and the inner member is fillable with a conductive fluid; ,
a first conductive wire and a second conductive wire extending along the length of the device within the volume between the outer covering and the inner member and terminating proximate a distal end of the device; a conductive wire, wherein lengths of the first and second wires are insulated and non-insulated at each of the first and second wires near distal ends of the first and second wires; a first conductive wire and a second conductive wire;
a conductive emitter band surrounding the ends of the first and second wires, the conductive emitter band having a first spark between the ends of the first wire and the emitter band; forming a gap, forming a second spark gap between the end of the second wire and the emitter band, filling the volume with the conductive fluid, and applying a high voltage pulse to the first and second spark gaps; a conductive emitter band, wherein when applied across two wires, first and second shock waves are initiated from the first and second spark gaps.
(Item 2)
2. The device of item 1, further comprising an insulating sheath surrounding the inner member in a region proximate ends of the first and second wires.
(Item 3)
2. The device of item 1, wherein the outer covering comprises an angioplasty balloon.
(Item 4)
2. The device of item 1, wherein the emitter band is a cylindrical tube that extends closer to the distal end of the device than the ends of the first and second wires.
(Item 5)
a fluid pump connected to the proximal end of the device and configured to provide conductive fluid to the volume between the outer covering and the inner member;
a fluid return line having an inlet proximate the distal end of the device and configured to remove the conductive fluid from the volume between the outer sheath and the inner member; 2. The device of item 1, wherein the fluid pump and fluid return line are configured to circulate the conductive fluid within the volume between the outer jacket and the inner member under pressure.
(Item 6)
6. The device of item 5, further comprising a pressure relief valve at the outlet of the fluid return line.
(Item 7)
a third conductive wire and a fourth conductive wire extending along the length of the device and terminating proximate the distal end of the device within the volume between the outer covering and the inner member; conductive wires, wherein lengths of the third and fourth wires are insulated and non-conductive in each of the third and fourth wires near the distal ends of the third and fourth wires. a third conductive wire and a fourth conductive wire, wherein there are insulating portions, the conductive emitter band surrounding the ends of the third and fourth wires, and the conductive emitter band surrounding the ends of the third and fourth wires; forming a third spark gap between an end of the wire and the emitter band; forming a fourth spark gap between the end of the fourth wire and the emitter band; and forming a fourth spark gap between the end of the wire and the emitter band; When filled with a conductive fluid and a second high voltage pulse is applied across said third and fourth wires, third and fourth shock waves are generated from said third and fourth spark gaps. The device according to item 1, wherein the device is initiated.
(Item 8)
2. The device of item 1, wherein the conductive fluid comprises saline or a combination of saline and a contrast agent.
(Item 9)
2. The device of item 1, further comprising one or more secondary emitter bands disposed at an intermediate location of the device and configured to initiate a third shock wave from the intermediate location.
(Item 10)
The device of item 1, wherein the inner member includes a guidewire lumen.
(Item 11)
A method for treating vascular plaque, the method comprising:
introducing a shock wave device into the patient's vasculature, the shock wave device comprising:
an outer covering;
an inner member, wherein the outer sheath and the inner member are connected to a distal end of the device, and a volume between the outer sheath and the inner member is filled with a conductive fluid;
a first conductive wire and a second conductive wire extending along the length of the device within the volume between the outer covering and the inner member and terminating proximate a distal end of the device; a conductive wire, wherein lengths of the first and second wires are insulated and non-insulated at each of the first and second wires near distal ends of the first and second wires; a first conductive wire and a second conductive wire;
a conductive emitter band surrounding the ends of the first and second wires, forming a first spark gap between the ends of the first wire and the emitter band; a conductive emitter band forming a second spark gap between the ends of the second wire and the emitter band;
advancing the shockwave device into the vasculature such that a distal end of the shockwave device faces a first treatment region;
applying a high voltage pulse across the first and second wires to initiate first and second shock waves from the first and second spark gaps.
(Item 12)
the outer covering comprises an angioplasty balloon, and the method further comprises:
After the applying step, further advancing the shockwave device into the blood vessel such that the angioplasty balloon is aligned with the first treatment region;
and inflating the angioplasty balloon.
(Item 13)
the outer covering comprises an angioplasty balloon, and the method further comprises:
After the applying step, further advancing the shockwave device into the blood vessel such that the angioplasty balloon is aligned with a second treatment region;
and inflating the angioplasty balloon.
(Item 14)
The shockwave device further comprises one or more secondary emitter bands disposed at intermediate locations of the device, and the method further comprises:
After the applying step, further advancing the shock wave device into the blood vessel such that an intermediate location of the one or more secondary emitter bands is aligned with the first treatment region;
and initiating a third shock wave from the one or more secondary emitter bands.
(Item 15)
The shockwave device further comprises one or more secondary emitter bands disposed at intermediate locations of the device, and the method further comprises:
After the applying step, further advancing the shock wave device into the blood vessel such that an intermediate location of the one or more secondary emitter bands is aligned with a second treatment region;
and initiating a third shock wave from the one or more secondary emitter bands.
(Item 16)
12. The method of item 11, wherein the tube is a blood vessel of the patient's vasculature or a ureter of the patient's urinary system.
(Item 17)
12. The method of item 11, wherein the first treatment area comprises chronic total occlusion (CTO), peripheral calcium, or kidney stones.

FIG. 1 depicts a cutaway perspective view of an exemplary shockwave device for generating forwardly directed shockwaves, according to some embodiments.

FIG. 2 depicts a side cross-sectional view of an exemplary shockwave device for generating forwardly directed shockwaves, according to some embodiments.

FIG. 3 depicts a front cross-sectional view of an exemplary shockwave device for generating forwardly directed shockwaves, according to some embodiments.

FIG. 4 depicts an expanded side cross-sectional view of an exemplary shockwave device for generating forwardly directed shockwaves, according to some embodiments.

FIG. 5 depicts an extended length side view of an exemplary shockwave device, according to some embodiments.

FIG. 6 is a flowchart representation of an exemplary method for generating a forwardly directed shock wave.

(detailed explanation)
Generating shock waves that propagate in a substantially anterior direction to treat vascular diseases such as chronic total occlusion (CTO) or peripheral calcium, or to treat urinary tract diseases such as stones in the ureter or kidney stones Described herein are devices, systems, and methods for. According to the present disclosure, a shock wave device includes an outer covering and an inner member defining a guidewire lumen. The outer sheath and inner member are connected at the distal end of the device. A first conductive wire and a second conductive wire extend along the length of the device within the volume between the outer sheath and the inner member and proximate the distal end of the device. finish. A conductive emitter band surrounds the ends of the first and second wires, forming a first spark gap between the ends of the first wire and the emitter band; A second spark gap is formed between the part and the emitter band.

When the volume is filled with a conductive fluid (e.g., saline and/or an imaging contrast agent) and a high voltage pulse is applied across the first and second wires, the first and second shock waves are generated. can be initiated from the first and second spark gaps. The voltage can range from 100 to 10,000 volts over various pulse durations. This high voltage generates a gas bubble at the end face of the wire, causing a plasma arc of current to traverse the bubble to the emitter band, producing a rapidly expanding and collapsing bubble, which in turn causes the device to A mechanical shock wave may be generated at the distal end. The positioning of the emitter band in relation to the end of the wire may result in a shock wave propagating in a substantially forward direction toward the distal end of the device. The shock wave is mechanically conducted through the conductive fluid and through the outer covering in a substantially anterior direction to apply a mechanical force or pressure to affect the occlusion or calcium facing the distal end of the device. You can. The bubble size, expansion and collapse rate (and therefore the magnitude, duration and distribution of the mechanical force) depend on the magnitude and duration of the voltage pulse and the distance between the end of the wire and the emitter band. may vary based on The emitter band may be made of a material that can withstand the high voltage levels and intense mechanical forces generated during use (eg, about 1,000-2,000 psi or 68-136 ATM for a few microseconds). For example, the emitter band may be made from stainless steel, tungsten, nickel, iron, steel, and the like.

FIG. 1 depicts a cutaway perspective view of an exemplary shockwave device 100 for generating forward-directed shockwaves, according to some embodiments. Device 100 includes an outer sheath 102 (eg, a flexible outer tube) and an inner member 104 that forms a lumen for a guidewire 114. Outer sheath 102 and inner member 104 are connected at the distal end of device 100 and guidewire 114 may exit device 100. The internal volume of device 100 between outer covering 102 and inner member 104 may be filled with a conductive fluid (eg, saline and/or imaging contrast agent). Two insulated conductive wires 106 (eg, insulated copper wires) extend along the length of device 100 within the interior volume. Although only one wire 106 is visible in FIG. 1, a second wire 106 extends along the opposite side of the inner member 104, as shown in FIGS. 2-3. Two wires 106 terminate near the distal end of device 100 where the guidewires exit the lumen formed by inner member 104. The ends of the two wires 106 include uninsulated portions (not shown). For example, the flat circular surfaces at the ends of two wires may not be insulated. An emitter band 108 is positioned within the interior volume around the ends of the two wires 106. The emitter band 108 may be a conductive cylinder with a diameter greater than the combined diameter of the inner member 104 and the two wires 106 to which it is coupled, such that the emitter band has a diameter as shown in FIG. Wrap around the ends of the two wires 106 without touching the wires. An insulating sheath 110 (eg, polyimide insulator) may be positioned around the inner member 104 to separate the two wires 106 from the inner member 104 and further insulate the two wires 106 from each other. Thus, the preferred conductive path between the two wires 106 is through the emitter band 108. When a high voltage pulse is applied across the two wires 106, a current arcs from the uninsulated end of one wire to the emitter band 108, and then again from the emitter band 108 to the other wire. arc to the uninsulated end of the As a result, a shock wave is initiated at the distal end of the shock wave device 100, which then propagates through the conductive fluid and the wall of the outer covering 102 to affect the occlusion or calcification.

In some embodiments, device 100 may include a second pair of wires (not shown) offset by 90 degrees from wires 106. For example, if the wires 106 are positioned at 0 degrees and 180 degrees, the second pair of wires may be positioned at 90 degrees and 270 degrees. The second pair of wires also terminate near the distal end of device 100 and include uninsulated portions at their ends. Emitter band 108 similarly wraps around the second pair of ends of the wire. A separate high voltage pulse may be applied across the second pair of wires to generate a second pair of arcs using emitter band 108. As a result, a second set of shock waves is initiated from the distal end of device 100. The first pair of wires 106 and the second pair of wires may be activated alternately, which may improve the effectiveness of the device 100 by further spreading the shock wave.

A fluid return line 112 with an inlet near the distal end of device 100 draws conductive fluid from the internal volume, while a fluid pump (not shown) has a fluid inlet at the proximal end of device 100 (see FIG. 5). (shown). In this manner, the fluid return line 112 and fluid pump circulate conductive fluid within the interior volume under pressure. Circulation of the conductive fluid may prevent air bubbles generated by the device 100 from becoming trapped within the distal tip of the device 100 due to the limited space within the tip. Additionally, circulation of conductive fluid may assist in cooling the device 100 and treatment site.

FIG. 2 depicts a side cross-sectional view of an exemplary shockwave device 100 for generating forward-directed shockwaves, according to some embodiments. As shown in FIG. 2, two conductive wires 106 (eg, polyimide insulated copper wires) are positioned along opposite sides of inner member 104. Each wire 106 includes an uninsulated wire end 202. An insulating sheath 110 (e.g., polyimide tubing) is positioned in the area proximate the uninsulated wire ends 202 to reduce the likelihood that electrical current will arc from one wire end to the other wire end. . The emitter band 108 is arranged with an edge forward of the wire ends 202 proximate the distal end of the device 100 such that two spark gaps are formed between each of the wire ends 202 and the emitter band 108. It is positioned in Positioning the wire ends 202, the insulating sheath 110, and the emitter band 108 means that when a high voltage pulse is applied across the two wires 106, current flows from the uninsulated end of one wire to the emitter band 108. The arc is then caused to strike again from the emitter band 108 to the uninsulated end of the other wire. As a result, a shock wave is initiated at the distal end of the shock wave device 100, which then propagates through the conductive fluid and the wall of the outer covering 102 to affect the occlusion or calcification. Positioning emitter band 108 closer to the distal end of the device than wire end 202 causes shock waves to propagate in a substantially forward direction (e.g., longitudinally out of the distal end of device 100). It helps to encourage Shock waves may be generated repeatedly, as may be desired by a practitioner to treat areas of the vasculature.

FIG. 3 depicts a front cross-sectional view of an exemplary shockwave device 100 for generating forwardly directed shockwaves, according to some embodiments. As shown in FIG. 3, emitter band 108 surrounds two conductive wires 106 (eg, insulated copper wires) and fluid return line 112. As shown in FIG. Fluid return line 112 includes an inlet that draws conductive fluid from the internal volume of the device and allows conductive fluid to be circulated within the distal end of device 100.

FIG. 4 depicts an expanded side cross-sectional view of an exemplary shockwave device 100 for generating forwardly directed shockwaves, according to some embodiments. As shown in FIG. 4, in some embodiments, the outer covering of device 100 includes an angioplasty balloon 402. Balloon 402 may be inflated by pumping additional fluid into the internal volume of the device. Balloon 402 may be inflated before or after applying shock waves to the treatment area. For example, in some embodiments, a forwardly directed shock wave is initiated using the emitter band 108 at the distal end of the device 100, and after disrupting the occlusion, the device 100 is directed into the patient's blood vessel. Further advanced, balloon 402 is inflated within the area of occlusion to further treat the area.

In some embodiments, shock wave device 100 may include a secondary emitter band 404 located within an intermediate location of device 100. Although the device 100 shown in FIG. 4 includes two secondary emitter bands 404, various numbers of secondary bands 404 may be used. For example, in some embodiments, device 100 may include a single secondary emitter band 404. In other embodiments, device 100 may include five or more secondary emitter bands 404. Secondary emitter band 404 may generate shock waves using various techniques. For example, secondary emitter band 404 is described in U.S. Patent No. 8,888,788 and U.S. Application No. 15/346,132, which are incorporated herein by reference in their entirety. Shock waves may be generated using thin or coplanar electrodes, such as those shown in FIG. The shock wave may radiate substantially radially from a location intermediate the secondary emitter band 404. In some embodiments, secondary emitter band 404 may initiate shock waves independently of emitter band 108 at the distal end of device 100. For example, in some embodiments, a forwardly directed shock wave is initiated using the emitter band 108 at the distal end of the device 100 and, after dissolving the occlusion, the device 100 It is advanced further into the patient's blood vessel until the intermediate location is aligned with the area of occlusion. Additional shock waves may then be initiated from the secondary emitter band 404 to further treat that area. Additional conductive wires may be provided between the high voltage source and the secondary emitter band 404 to enable independent operation.

In some embodiments, forwardly directed shock waves from emitter band 108, radially directed shock waves from secondary emitter band 404, and inflation of angioplasty balloon 402 are utilized in various sequences and combinations; Plaques or occlusions within the duct may also be treated. The duct may include a blood vessel within the patient's vasculature or a ureter within the patient's urinary system.

FIG. 5 depicts an extended length side view of an exemplary shockwave device 100, according to some embodiments. Shockwave device 100 may be in fluid communication with a fluid source and a fluid pump (not shown) that introduces conductive fluid into the internal volume of device 100 via fluid inlet 502. A fluid pump may fill an internal volume with fluid up to a certain pressure. Conductive fluid may be circulated within the interior volume of device 100 by drawing the fluid into the fluid return line shown in FIGS. 1 and 3 and then purging it through waste outlet 504. Waste outlet 504 may include a pressure relief valve to maintain fluid pressure within the internal volume of the device while conductive fluid is circulated. Circulation of the conductive fluid may prevent air bubbles generated by the device 100 from becoming trapped within the distal tip of the device 100 due to the limited space within the tip. Trapped air bubbles may block subsequent shock waves from propagating out of the device 100, so preventing their accumulation is beneficial. In some embodiments, waste outlet 504 may be connected to a fluid source such that a fluid pump recirculates waste fluid.

FIG. 6 is a flowchart representation of an exemplary method for generating a forwardly directed shock wave. As depicted in FIG. 6, a shock wave device is introduced into the tube (602). The duct may include a blood vessel within the patient's vasculature or a ureter within the patient's urinary system. The shockwave device may be device 100, described with reference to FIGS. 1-5. A shockwave device is advanced into the canal so that the distal end of the device faces the first treatment area (604). The first treatment area may include chronic total occlusion (CTO), peripheral calcium, kidney stones, or other occlusions or stones. Once the distal end of the shock wave device is facing the first treatment area, a high voltage pulse is applied across the first and second wires and the emitter band. (606) initiating first and second shock waves from first and second spark gaps formed between the first and second spark gaps. Due to the positioning of the first and second wires and the emitter band, the first and second shock waves propagate from the shock wave device in a substantially forward direction and impact the occlusion or calcium within the first treatment area. effect. In some embodiments, the shockwave device may then be advanced further into the vessel such that the angioplasty balloon is aligned with the first treatment region or the second treatment region (608). The angioplasty balloon may then be inflated within the first or second treatment region (610). In this manner, a conventional angioplasty balloon procedure may be applied after the shockwave procedure has been applied to treat one or more treatment areas. Alternatively, or in addition, in some embodiments, the shockwave device is further positioned within the canal such that the secondary emitter band at the intermediate location of the device is aligned with the first treatment region or the second treatment region. It may be advanced (612). A third shock wave may then be initiated from the secondary emitter band to apply an additional shock wave to treat the first or second treatment area (614). Steps 604-614 may be performed in various sequences or combinations and repeated as necessary, as appropriate to treat the patient.

Although the invention has been particularly shown and described with reference to embodiments thereof, it will be appreciated by those skilled in the art that various changes in form and detail may be made without departing from the scope of the invention. There will be. For all of the embodiments described above, the steps of the method need not be performed sequentially.

Claims (12)

A catheter for treating occlusion in a blood vessel, the catheter comprising:
a tubular inner member;
an emitter assembly, the emitter assembly comprising:
a first insulated wire extending along the length of the inner tubular member and having an uninsulated distal surface;
a second insulated wire extending along the length of the tubular inner member and having an uninsulated distal surface, the second insulated wire extending circumferentially from the first insulated wire; a second insulated wire that is offset;
a conductive sheath surrounding a distal end of the first insulated wire and a distal end of the second insulated wire, the first spark gap being between the conductive sheath and the first insulated wire; a conductive sheath extending between the uninsulated distal surface and a second spark gap extending between the conductive sheath and the uninsulated distal surface of the second insulated wire; an emitter assembly comprising;
a flexible member sealably attached to the distal end of the catheter and surrounding the emitter assembly, the flexible member being fillable with a conductive fluid; When filled with a conductive fluid and a high voltage pulse is applied across the first and second insulated wires, first and second shock waves are initiated from the first and second spark gaps. A catheter comprising: a flexible member; The catheter of claim 1, wherein the second insulated wire is circumferentially offset from the first insulated wire by 180 degrees. 2. The distal end of the conductive sheath extends distally beyond the uninsulated distal surface of the first insulated wire and the uninsulated distal surface of the second insulated wire. Catheter described in. 2. An insulating sheath surrounding the tubular inner member in a region proximate the uninsulated distal surface of the first insulated wire and the uninsulated distal surface of the second insulated wire. catheter. a fluid pump connected to the proximal end of the catheter and configured to provide the conductive fluid to fill the flexible member;
a fluid return line having an inlet proximate the distal end of the catheter and configured to remove the conductive fluid from the flexible member, the fluid pump and the fluid return line comprising: 2. The catheter of claim 1, wherein the catheter is configured to circulate the conductive fluid inside the flexible member under pressure. 6. The catheter of claim 5 , comprising a pressure relief valve at the outlet of the fluid return line. 2. The catheter of claim 1, wherein the conductive fluid comprises saline or a combination of saline and contrast agent. The catheter of claim 1, comprising one or more secondary conductive sheaths disposed at an intermediate location of the inner tubular member and configured to initiate a shock wave from the intermediate location. The catheter of claim 1, wherein the tubular inner member includes a guidewire lumen. a third insulated wire extending along the length of the inner tubular member and having an uninsulated distal surface;
a fourth insulated wire extending along the length of the tubular inner member and having an uninsulated distal surface, the fourth insulated wire extending circumferentially from the third insulated wire; a fourth insulated wire that is offset, the conductive sheath surrounding a distal end of the third insulated wire and a distal end of the fourth insulated wire; a gap extends between the conductive sheath and the uninsulated distal surface of the third insulated wire, and a fourth spark gap extends between the conductive sheath and the uninsulated distal surface of the fourth insulated wire. 2. The catheter of claim 1, wherein the catheter extends between the catheter surface and the surface of the catheter. 11. The catheter of claim 10 , wherein the fourth insulated wire is circumferentially offset from the third insulated wire by 180 degrees. 12. The catheter of claim 11 , wherein the third insulated wire is circumferentially offset from the first insulated wire by 90 degrees.